The current small-size generators widely use column type generators, a center is manufactured into a rotor with coils, single coils on a side wall cut magnetic force lines, the generators consume a large amount of copper, inner rotors are difficult to radiate, irreversible demagnetization occurs at high temperature if permanent magnets are used in the rotors, and thus the performance of the generator is reduced, a stator assembly is difficult to radiate, and the size of the stator is limited.
A disk type electric machine was invented by Faraday in 1821, stators and rotors of the disk type electric machine are of plane disk structures, and the stators and the rotors are axially and alternatively arranged. Due to limitation of materials and technological level at that moment, the disk type electric machine cannot be further developed. With the increasingly outstanding of energy and environment problems, the new energy has gradually become the focus of people's attention. Especially, wind electricity, as one of new energy industries having the most mature and commercialized development prospect at the present stage, has gained high concern and attention from governments of all countries and companies. Especially for a small-size wind turbine system, it is high in maneuverability and flexible to use, not only has a wide development prospect in remote areas, such as pasturing areas, fishing boats and sea islands, but also has incomparable advantages on small-power electric equipment for urban illumination, monitoring and the like. The disk type electric machine is simple and compact in structure, small in volume and high in torque density, especially, for a disk type permanent magnet electric machine with a double-outer rotor stator-free core, cogging torque and stator iron loss are eliminated, pull-in torque is low, and efficiency is high; a power machine can be directly mounted on the outer rotor, and the system is simple and reliable.
The magnetic flux density and the power density of the disk type stator of the existing laminated generator still need to be further improved. Although a superposition use solution of a disk type electrical machine has been proposed, there are no distinct basis and parameter conclusions rendering the disk type electric machine to surpass the traditional cylinder type generator in the aspects of use and effects. The structure requirements of the laminated generator are slightly different from those of a disk type motor in that the laminated generator drives the rotors to rotate with relatively small rotational inertia to the greatest extent and outputs electric energy, and its volume and weight are as small as possible so as to facilitate application.